Research On The Performance And Parameters Identification Of A Six-axis Accelerometer

Six-axis accelerometer which can measure the six-axis accelerations of the moving object at thesame time has wide application prospects in inertial navigation, the attitude control of the robots, therollover warning of the vehicles and some other fields. The parallel mechanism shows manyadvantages such as high stiffness, good structural stability, large load-carrying capacity and so on.Based on these points, our research team designed a piezoelectric six-axis accelerometer based on the9-SPS redundant parallel mechanism. The thesis researches the performance and parametersidentification method for this9-SPS piezoelectric six-axis accelerometer. The main research contentsare as follows:Firstly, the decoupling processes of the9-SPS piezoelectric six-axis accelerometer were deepanalyzed. In order to research the input/output characteristics of the six-axis accelerometer, and theerror sensitivity of the six-axis accelerometer’s main parameters, a model of this9-SPS piezoelectricsix-axis accelerometer was built in ADAMS, and the results can be used in the parametersidentification processes. Based on the general single-axis sensor’s performance indicators andcombined with the characteristics of parallel mechanism, the performance indicators of the six-axisaccelerometer were defined. Secondly, the retrieved vibration tables which can be used as anexperimental platform for the six-axis accelerometer were deep analyzed and compared. Theproblems of the existing vibration tables and the necessary characteristics of the ideal experimentalplatform for the six-axis accelerometer have been summarized. Based on these, a new type ofexperimental platform has been designed. This experimental platform has the following advantages,it’s easy to be controlled, it can ensure the installation of the standard sensor and the six-axisaccelerometer which need to be researched, it can produce pure linear motion/pure rotation/combinedmotion, it can be used to incentive those six-axis accelerometers which don’t produce output for theconstant acceleration input. That’s to say, it can translate the uniform rotation of the motors to theideal output with changing acceleration. Thirdly, in view of the acceleration decoupling principle ofthe six-axis accelerometer and the error sensitivity of the9-SPS piezoelectric six-axis accelerometer’smain parameters, an algorithm used on the parameters identification and an error compensationsolution were proposed. Finally, some experiments were designed and conducted based on theexperimental platform, and all the values of the performance indicators have been acquired.The experimental platform designed in this paper can be applied to the six-axis accelerometers which don’t produce output for the constant acceleration input. The parameters identification methodcan be used as a reference for other types of six-axis accelerometer. The research work in this thesishas some practical value for the further development of the six-axis accelerometer.